Ethernet type networks have been used in communication networks for implementing communication among various network components. An Ethernet network may be used to send or route data in a digital form by packets or frames. Each packet contains a set of data, and the packet is generally not interpreted while sent through the Ethernet network. The Ethernet network is typically composed of different equipment that subscribes to the network and connects to each other through switches. Each network subscriber can send packets in digital form generally at any time to one or more other subscribers. When a switch receives the packets, the destination equipment is determined, and the packets are switched to such equipment. In a switched full-duplex Ethernet type network, the term “full-duplex” refers to sending and receiving packets at a same time on a same link, and the term “switched” refers to the packets being switched in switches on appropriate outputs.
Avionic systems generally include numerous components that may exchange data among one or more other components. For example, a variety of external sensors may gather information that is routed via an avionics network to a number of different aircraft components. In avionic systems, redundant networks are common design considerations. More recently, Ethernet networks have been used in avionic network environments. For example, Aeronautical Radio Inc. (ARINC) 664 regarding avionics full duplex switch Ethernet networks, or more commonly referred to as AFDX, sets forth an aeronautical standard that defines a dual redundant avionics network for use in an aircraft environment.
In an aircraft environment, any number of different line replaceable units (LRUs) may be connected to an avionic network. One method of connecting an LRU to a network is using either an “A” network, a “B” network, or both networks to transmit and receive messages. Messages sent on both networks, such as an original message and a redundant copy of the original message, are typically selected at the destination end system using “First Arrival Wins,” and the redundant copy may be discarded.
When connecting an LRU to an AFDX network, a common method is to couple the LRU via point-to-point wiring to a switch of each of the “A” and “B” networks. This method generally creates a significant number of connections to the AFDX network that results in an equally significant cost for each port and wiring that is associated with each connection. Each of the switches may be designed to couple to more than one LRU. In the event of failure of one of the switches (e.g., the “A” network switch), communication may continue among the LRUs coupled to the other switch (e.g., the “B” network switch). In some configurations, the destination LRU is coupled to switches of the “A” and “B” network (e.g., a second switch of each of the “A” and “B” networks) that are different than the respective switches of the “A” and “B” network that are coupled to the origination LRU. These “A” and “B” network switches of the destination LRU are in turn coupled to the “A” and “B” network switches, respectively, of the origination LRU, such as via a communication bus. When one of the switches coupled to the origination LRU fails (e.g., the “A” network switch), the message may be transmitted to the destination LRU using the other switch (e.g., the “B” network switch). When both switches coupled to the origination LRU fail, the origination is prevented from communicating with the destination LRU.
Accordingly, it is desirable to provide a redundant avionics network having improved redundancy and capability to dispatch with one or more communication system failures. It is also desirable to method for switching communications in an avionics network having improved redundancy and capability to dispatch with one or more communication failures. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.